You can think of sensory integration (SI) as the foundation from which all other skills are built. In order to achieve developmental milestones children must first be able to take sensory input in, process it, and respond to it within seconds. We take in and process huge amounts of sensory input each minute. Frequently, however, children have difficulty with either taking the input in or responding to it. This difficulty can cause delays in gaining new skills until the child wires his brain to process and respond to the sensory input smoothly.

The Basics

We all know the five senses: sight, smell, taste, hearing, and touch. When we discuss SI we add to it the two senses of vestibular (response to movement) and proprioception (body awareness). In a typically developing sensory system children and adults are able to take in all forms of sensory input at the same time, process it, and respond to it within a second or two.

Children who have difficulty processing some of these forms of sensory input experience it in one of two ways. Some children have a bit of âindigestion.â Imagine eating cold leftover pizza at three in the morning while trying to finish some work. In a similar way, certain pieces of input do not agree with children: touching messy things, going on car rides, being in loud places, taking baths. When children with sensory âindigestionâ take these pieces of stimulation in they react negatively by doing repetitive things, becoming aggressive, becoming upset, withdrawing, etc.

Some children have a âtraffic jamâ response. Weâve probably all experienced trying to merge into traffic on the highway in the height of rush hour. Now add to that construction in the right lane and a broken down car in the left lane. Can you picture the bottleneck and stress of three lanes of cars merging into one? It would be enough to shut down the highway. Childrenâs sensory systems are always under construction and often times they get a break down in one lane (from the indigestion response). These kids often shut down until they can sort through the sensory input calmly and put everything in the right spot in their mind.

Children who have an indigestion response are often able to remain around the input, but they appear to shut other sensory receptors down. This allows a child to focus all of his energy on processing the input that causes a little difficulty. For instance, if a child has some fears about touching messy things, he or she may not respond to your questions, make eye contact, or he or she may even drool while poking at pudding.

Children who experience a traffic jam response often try to completely remove themselves from sensory input when it becomes too intense. Their system shuts down for a few seconds or minutes, and they move to quiet, safe places where there is very little in terms of input (dark, quiet room with their favorite blanket, etc.) Alternately, they may become inconsolable or aggressive and seem to become more upset with your attempts to calm them. After their sensory system resets, they are able to return, but may have to quickly remove themselves again. In the traffic jam response the childâs fight or flight response takes over; they may become aggressive or run from the situation just as we would if we turned the corner and walked into a 9-foot tall black bear.

Difficulties Versus Quirks

We all have our little difficulties when it comes to processing sensory input; we might not eat seafood because of the texture, avoid roller coasters, avoid walking barefoot, etc. No sensory system is âperfect.â We all have our little quirks; if not weâd be pretty boringâ¦all the same.

Children have their own little quirks too; the difference between a quirk and a sensory processing difficulty is that a sensory difficulty interferes with our daily life. It prevents us from achieving new things and growing developmentally.

Quirks do not pose any great concerns and most children will outgrow or adapt to a quirk. Difficulties, however, show a need for intervention. A child will seek out what they need, but they may not be able to get the intensity they require and will consequently not seek out a nice balance of activities. This imbalance can cause one of their other sensory areas to suffer and cause more difficulties for the child. Occupational Therapists (OTs) are able to distinguish between quirks and difficulties by observing the child, asking questions and having the family/caregivers fill out a Sensory Profile. The Sensory Profile does not âdiagnoseâ a sensory processing difficulty; it only helps the therapist to focus the therapy on the most needed areas and cuts down on the trial and error approaches.

Sensory Diet

We all need a balanced diet both in what we eat and what we take in with our sensory experiences. We donât feel well if we eat poorly, and children who do not have a balanced sensory diet will respond poorly to their environment. One of the basic theories in Sensory Integration is that our bodies are drawn to what they âneedâ; however, sometimes children cannot achieve the level of intensity that their system requires. They may seek out input in dangerous or unacceptable ways. This causes an unbalanced diet, which makes it difficult to build advanced skills.

Take for example the child who is on the go all day long: running, dancing, rocking. They are seeking out movement input but are unable to achieve the level of intensity they require to move on and improve their ability to process movement input. The child spends so much time seeking out movement input that they donât play much with their hands. This causes their touch receptors to stay at their level of processing and adds to the difficulties they have with movement (we have to touch to climb, etc.) In other words the childâs sensory processing difficulties snowball on top of one another and prevent the child from achieving new milestones.

One, Two and Three Object Play

Sensory processing develops sequentially for all children. They show interest in their environment in a continually progressive way.

One object play: When children are newborns, they kick their legs, flap arms, bat at toys, etc. The child sees his body as an object. At this stage the childâs sensory system is turned inward. They may be aware of what is going on around them but do not necessarily seek out interaction.

Two-object play: The child now brings another object into their play (a toy or person). The child manipulates toys or interacts with people. The child is an object, and the toy or person is an object. At this stage the child is able to concentrate on what he does to a toy, or what he does with a person, but not both at the same time. The childâs sensory system is beginning to unfold. He realizes he has an effect on the environment and can do a lot of cause and effect actions.

Three-object play: This is the most advanced stage. The child sees himself as an object, a toy as an object, and another person as an object, all at the same time. For example, the child pushes a ball to an adult, the adult pushes it back. This goes on for a few repetitions and then the adult does not return the ball right away. If the child makes eye contact with the adult as if to ask, âWhatâs going on?â they have mastered three object play, which is integral to communication.

These stages are important for sensory processing because children must first become comfortable with themselves before becoming comfortable with the outside environment. As you see a child progress through these stages you can see how their sensory system is maturing.

Setting Up the Environment

Jean Ayres (who developed the concept of Sensory Integration) said that the easiest way to give a child a well-balanced sensory diet is to first find what they are seeking out and then set up the environment to encourage the child to explore that input. Below you will find the three major areas of Sensory Integration and descriptions of things you might see in children that are seeking these types of input. Remember, this doesnât mean you didnât offer them what they needed, or they are broken, it just means their brain needs more intense experiences to wire itself. Since a childâs sensory system will push them to the input they need to grow, you can try the exercise of writing down what a child does throughout a typical day. When you break your list into the categories of movement, body awareness, and touch you may see one column that is a lot longer than the others; this is what they need.

The key piece to setting up the environment is not forcing the child to do something (avoid hand over hand, the old âthrow them in, theyâll learn to swimâ). Instead, model the behavior you would like to see them do and wait for their response. In the beginning it usually works best if you expand out of an activity they are already doing and use as few words as possible (to cut down on distracting sensory inputs). If you want a child to play with textures, and they like playing with blocks, then start playing with blocks as well, before slowly putting them into the texture.

The other key piece in setting up a successful environment is to closely monitor a childâs response to sensory input. It is NOT a good idea to allow a child to over-stimulate himself or overload on a particular input and shut down. Overloading a personâs system does not foster development, it discourages a child. If you were practicing to run a mile and could make it part of the way, you would continue to go that distance until you could add to it. If a person made you keep running and you passed out or fell over from exhaustion, you would not run farther the next time. You would only have bad thoughts about running and avoid the situation. The same holds true for sensory systems so we try our hardest not to allow overloading and shutdown to happen; we change the input before overloading by monitoring the childâs responses and cues.

Tactile (Touch) Input and Processing

This is how a child responds to touch and feel with hands and body parts, as well as with the mouth.

The tactile system begins to be wired with the mouth: children pick things up and put them in their mouth the first few months of their life.

The hands are next: bearing weight helps to make the connections in all of the nerve pathways to the brain, so this step usually follows a child pushing up on hands while on his belly. Kids initially turn things over and over to feel them and then put them in their mouth to check their thoughts. Children later can distinguish by just their hands and then finally by sight for familiar textures.

Signs of difficulties with touch processing (again, it must affect their daily life):

Playing in two texture things such as cool whip and crumbled crackers together, wet sand, finger paint and rice krispies (This is an advanced skill and should be tried only after one texture play is mastered.)

Some children respond well to brushing, hand-sandwiches, lotion being rubbed on them, and being rubbed briskly with a dry washcloth.

Vestibular (Movement) Input and Processing

Signs of difficulties with processing movement input (again, it must affect their daily life):

The child runs, and runs, and runs, and runs, and runs, and you cannot get his attention.

The child climbs all the time.

The child can spin for minutes without getting dizzy.

The child loves to swing and becomes extremely upset when stopped, even after a long period of time.

The child hates to swing.

The child becomes upset driving in a car.

The child becomes very frightened when his head is tipped back.

The child is very frightened when his balance is challenged to the sides or back, especially.